Hitherto, as organic electrolyte cells having wound electrodes, for example, lithium graphite-fluoride cells and lithium manganesedioxide cells have been known. The organic electrolyte cells have excellent discharge characteristics and storage properties, and are hence widely used in applications momentarily requiring a large current such as a camera and a strobe, applications of long-term use such as memory back-up, and others. Recently, as these appliances are enhanced in performance, the organic electrolyte cells are also required to be further enhanced in discharge capacity.
In these cells, foils of an alkaline metal such as lithium or its alloy are used as negative electrodes. A conductive metal is used as the active material for the negative electrode. Accordingly, except for a lead-like current collector to be welded to the can, a conductive core not relating to the discharge reaction is not needed. Instead, the filling amount of the active material can be increased by a corresponding portion. However, if a difference in speed occurs in the discharge reaction due to non-uniformity of the partial active material amount or an imbalance of pressure applied to electrode plates, part of the negative electrode may be extremely consumed, and the electric connection between the current collector and the active material of negative electrode may be lost. As a result, at the end of discharge, due to a decrease in the reaction area of the negative electrode, a sudden drop of discharge voltage occurs. In particular, this discharge voltage drop is notable in the case of low current discharge.
The invention hence solves the problem of localized consumption of the organic electrolyte cell as described in the prior art, suppresses the voltage drop at the end of cell discharge, and presents an organic electrolyte cell of high performance having an excellent discharge capacity.